Epicardial fat in patients with metabolic syndrome: A systematic review and meta-analysis

Abnormally increased epicardial fat appears to be associated with an additional risk of major adverse cardiovascular events (MACEs) in the context of metabolic syndrome (MetS). However, evidence on the relationship between epicardial fat volumes (EFVs), epicardial fat thickness (EFT) and MetS remains inconsistent.

Specific searches of electronic databases from 1 January 2000 to 31 October 2022 were independently performed by two researchers. In this study, two quantification measures of epicardial fat were included: comparison of total computed tomography-based EFVs and EFT between two groups (individuals with and without MetS), estimating standardized mean difference (SMD) with corresponding 95 % confidence intervals (CIs) through a random-effects model analysis. The heterogeneity in the included studies was explored by meta-regression and subgroup analyses.

The EFVs were significantly increased in MetS subjects compared with non-MetS subjects (SMD: 1.07, 95 % CI: 0.69-1.45, p < 0.001), and the EFT was also significantly larger in MetS patients than in the Non-MetS (SMD: 1.12, 95 % CI: 0.84-1.41, p < 0.001). We compared the Caucasian and American subgroups with the Asian and African subgroups, and the EFT was greater in the former subgroups (SMD: 1.32, 95 % CI: 0.44-2.20, p < 0.001). When comparing the EFT among the age subgroups, there was a significant SMD between adolescents and adults or elderly individuals (SMD: 1.21, 95 % CI: 0.84-1.52, p < 0.001).

MetS patients tend to present greater EFT near the right ventricular free wall and greater total EFVs. Increased epicardial fat, an imaging biomarker, independently affects the onset of MetS.